"The strongest reason for people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government."- Thomas Jefferson

Thats the strongest reason right there, Jefferson hit the nail on the head, as he so often did.

If someone poo, poos the idea of tyrannical government, remind them of Stalin, Hitler, Pol Pot, etc, etc from just the 20th century alone. Many of those millions of dead people thought the government would protect them too.